U.S. Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, says NATO members must acknowledge the alliance is facing “multiple complex threats."

Members of NATO’s highest military authority were meeting Saturday in Istanbul, Turkey, to discuss security issues including the support mission in Afghanistan, the threat of Russian aggression on NATO’s eastern flank and the fight against the Islamic State militant group.

“I never try to convince them that one threat is more dire than another,” Dempsey told VOA. “What I want to make sure that they accept and concede is that there are multiple threats.”

He said host nation Turkey was playing a critical role in helping NATO “understand the issues” it faces.

Fight against IS

The war against the Islamic State is at Turkey’s doorstep, with nearly 2 million refugees fleeing violence in Syria by flooding into Turkey.

Analysts say disagreements between the Turkish and U.S. governments have allowed the Islamic State group to expand its reach.

“I think a lot of the unwritten story or partially written story of why we’re struggling so much in Syria these last couple of years is because the U.S.-Turkish relationship has struggled so much,” said Michael O’Hanlon, a defense policy expert at the Brookings Institution.

O'Hanlon, author of a new book, The Future of Land Warfare, said Turkey has tolerated "a lot of less than ideal" developments in its view, including the movement of IS fighters and supplies across its border, because the leadership in Ankara desperately wants to get rid of Syrian President Bashar al-Assad. While Turkey and the U.S. would both like to see Assad go, O'Hanlon said Turkey has been disappointed by watching the Obama administration do “almost next to nothing to make that happen.”

Turkey stepping up

Turkey has taken recent steps more in line with U.S. and coalition interests, first opening up its Incirlik airbase to U.S. warplanes in July, and later joining in coalition airstrikes against the militants. The U.S. has tried to gradually arm moderate opposition fighters in Syria to fight the Islamic State group, but the pace of the operation to train and equip anti-Assad forces has been so slow that opposition fighters are getting killed off or captured quickly, before others can join the fight.

“We bomb a few targets and we hope for the best. That’s not really a serious strategy,” said O’Hanlon. “Turkey and the United States may be getting along better, but they’re getting along better in support of what’s arguably a losing strategy.”

The U.S. says a number of factors — from leadership issues in Iraq to a shortage of reliable partners in Syria — have kept the Islamic State in the fight. The battle is expected to take years, even as Dempsey and other generals say the fight is “tactically stalemated.”